The present invention concerns a unit for making beverages by brewing of a dose of product to be brewed.
It also concerns an automatic machine for making beverages like espresso coffee, incorporating the unit described in the invention.
According to the invention, the unit comprises several brewing chambers, each provided with a receptacle for the dose and means for injecting hot water into each of the brewing chambers.
The invention will be particularly applicable to the field of making coffee-based beverages of the espresso type.
It may be used to build and operate an automatic machine that is very practical to use and highly productive.
Automatic unit for making espresso coffee are already known.
In that respect, the document EP-A-0.450.200 discloses an automatic unit for espresso coffee comprises a pressure chamber for the preparation of the coffee, this pressure chamber comprising a closing/opening element for the insertion and removal of the coffee powder and at least one adjustable movable wall defining the volume of the chamber.
In the document, the single brewing chamber is closed at the top by a pivoting element and at the bottom by a mobile piston.
The pivoting element can adopt an opened position to the admission or the evacuation of the ground.
However, the unit has the drawback of only making it possible to make a single coffee or a double coffee by increasing the quantity of grounds in the brewing chamber.
It does not allow associating several brewing chambers, which means that the efficiency of the machine is conventional, i.e. it only completes one brewing operation at a time.
Besides, the cost of this unit design is high, particularly because of the form of the mobile piston and the closing system at the top of the chamber.
It is also known the document EP-A-0.604.350, which describes a coffee machine that includes two receptacles with a dose of coffee each, two pistons that press down the said dose of coffee and two ejectors. The machine is used to prepare one or two coffees at the same time and three coffees if one of the receptacles has a double capacity and a double outlet. Each seat or base mounted to turn along with the main shaft has a cavity in which a support for a filter is positioned, through which the brew passes. The angular distance between the receptacles is the same as that of the pressure pistons so that they are opposite the said receptacles at the same time. The ejectors intended for the brewed coffee dose are fitted with the same angular distance.
Two brewing chambers can be formed according to this document by doubling all the essential meansxe2x80x94piston, receptacle and ejector.
Even though it provides for building two brewing chambers, the machine has the drawback of increasing the number of constituent parts required for that use.
For instance, all parts come in a pair which is heavy, complicated and costly.
Further, the machine only enables the coupled operating of the brewing chambersxe2x80x94if you wish to use them both, they must follow simultaneous identical cycles.
As a result, the machine does not make for flexible use.
The brewing chambers cannot in fact operate independently.
Document CH-A-674703 also discloses a machine with several brewing chambers.
The chambers move on a base with several holes for letting out the coffee of the used grounds, from each chamber.
The chambers move individually using a complex organization which does not enable fully simultaneous operation or making a common area for removing the used grounds.
Document U.S. Pat. No. 4,829,889 shows a highly specific application mechanism, where cartridges of ground coffee are made to move. A rotary part with holes is provided to move the cartridge from one station to another. There is only one brewing chamber and the working of the mechanism is closely related to the structure of the cartridges used.
The present invention is aimed at making up for the drawbacks of currently known unit and automatic coffee machines.
To do so, it has at least two brewing chambers that are opened and closed by a mobile plate with an orifice.
In that way, a unit is made with several brewing chambers, which increases productivity.
Further, the assembly unifies the machine in order not to multiply the number of constituent elements by the number of brewing chambers required.
According to the invention a simple machine is achieved with compact dimensions containing several brewing chambers.
The invention also offers the benefit of having different elements common to the brewing chambers, particularly the mobile plate or the automatic control means, that may be grouped.
The other aim of the invention is to make the use of the unit more flexible by enabling it to make just one brew or two simultaneous brews or even make a brew while the other chamber is being filled with coffee or emptied of the used grounds.
As a result, the present invention offers the possibility of working concurrently on several brewing chambers.
That adds flexibility to the productivity obtained.
Other aims and benefits will emerge during the description below, which is however not limitative.
The unit for making beverages by brewing of a dose of product to be brewed comprising several brewing chambers, each provided with a receptacle for the dose and means to inject hot water in each of the brewing chambers is characterised by the fact that the brewing chambers are juxtaposed and topped by a mobile plate with an orifice designed to be positioned opposite the brewing chambers for opening or closing the brewing chambers (1a, 1b) depending on its position.
The unit according to the invention may be embodied in the modes outlined below:
there is a seal between each brewing chamber and the mobile plate;
the injection means are composed of radial supply circuits that open out into each brewing chamber;
the lower wall of the receptacle is created by a mobile piston that moves between a position for receiving the dose to a position for ejecting the dose into the orifice when it is used;
the shape of the section of the orifice is identical to that of the opening of the brewing chambers, while its dimensions are slightly greater;
the perimeter of the orifice is at least as thick as the maximum height of the used dose ejected after brewing,
the used dose is ejected by gravity when the mobile plate moves;
the plate is a mobile disc rotating in a horizontal plane,
the said unit has two brewing chambers positioned under the plate so that they are in the path of the orifice;
it comprises the automatic means to load a dose of a product to be brewed, including:
an assembly for supplying the brewing product that opens out onto at least one supply channel,
a funnel that receives the dose by gravity from the supply channel/s, the lower end of which opens at the mobile plate,
the means to position the funnel above one of the brewing chambers in order to load a dose in one of the brewing chambers when the orifice is positioned above it;
the shape and dimensions of the lower end of the funnel are more or less similar to those of the openings of the brewing chambers;
the means to position the funnel opposite to one of the two brewing chambers comprise:
a vertical shaft pivot link with a return mechanism,
a driving pin fixed on the outer wall of the funnel that works along with an annular part on the perimeter of the mobile plate to direct the funnel into one of the three positions below:
the idle position when the driving pin is fitted in a notch formed on the annular part, the brewing chambers being placed symmetrically on either side of the idle position;
the position opposite to one of the brewing chambers when the driving pin presses on the portion of the annual part that is located on the first side of the notch;
the position opposite to the other brewing chamber when the driving pin presses on the portion of the annular part that is located on the other side of the notch;
the means to make the funnel vibrate in order to make the brewing material drop down.
at least one area of each portion of the annular part is raised to make the funnel vibrate when the driving pin passes over it;
the means to clean the orifice when the used dose is removed, including the following:
a weight, the section of which has the same shape and is slightly smaller than the section of the orifice,
the means to suspend the weight so that it can be moved in and out of the orifice.
the suspension means include:
a horizontal shaft pivot link,
an articulation to lower or raise the weight so as to insert it into the orifice and take it out when the mobile plate moves;
the weight has a sectional profile in order to facilitate insertion into and removal from the orifice;
the weight is fitted on a rod connected to the horizontal shaft pivot by an annular linear link in order to make it easier for it to move in and out of the orifice.
The invention also concerns an automatic machine for making espresso type beverages with at least one unit as described in the invention.